Two Female JRTs

Question
I have two female JRT's that have pretty muich been raised together from the time they were puppies. They are now 2 and 1 1/2 years old and as they have gotten older I have noticed that they have become more active with their "rough" play and even a little bit aggressive. I just read somewhere recently that two dogs of the same gender are not really recommended with this breed and would like to know if that really is the case and if so what would be something I can do to perhaps break up the focus on eachother so no one gets hurt. They are always kept seperate during the day when I am away and are otherwise out and about with each other the rest of the time and under supervision. They get along great and only seem to get aggressive when they haven't yet had a physical outlet. Other than that they seem to do just fine together.

Answer
Hi Natalie

I have four females that live together and they get along just fine.
I don't place a lot of credence in the rumor of the same sex not getting along. You are doing everything right by making sure they get enough exercise to burn some of that energy off, and keeping them separated when you aren't there is a good idea too.  What you need to do is immediately stop the very first sign of aggression you see happening (like if they make a little growl, a stare down, a curled lip). A QUICK, DIRECT but simple assertive noise or touch (poke with meaning) or command by you to the aggressor will break that concentration and redirect the behavior. Try very hard to stop it the SECOND you see it, don't allow either of them to show one single sign of aggression without an immediate correction. Use the same voice and touch command every time, and eventually they will get so used to that sound that you will be able to do it from across the room without the touch. Stay consistent and assertive and IN COMMAND.
You are the boss.
Best of luck, I know you can do it!
Take care